The ability of observers to extract depth from opposite luminance-contrast-polarity stimuli was investigated. The stimuli consisted of two dichoptic-pairs of Gaussians, with one of the Gaussians in each pair having a positive contrast-polarity and the other a negative contrast-polarity. Stimulus durations ranging from 0.2 to 4 s were used. This range of durations was employed to reveal stereo m...

To elucidate the discriminating processes of surface depth and boundary form in global stereopsis, event-related brain potentials (ERPs) were investigated by the detection of combinations of the attributes in random sequences. The attentional relevance of depth or form was associated with selection negativities (SNs) over the lateral occipito-temporal regions initiating at about 200 ms post-sti...

We propose a real-time fingertip detection algorithm based on depth information. It can robustly detect single fingertip regardless of the position and direction of the hand. With the depth information of front view, depth map of top view and side view is generated. Due to the difference between finger thickness and fist thickness, we use thickness histogram to segment the finger from the fist....

PURPOSE The two pencil test (TPT) checks the ability to perform a simple visual-motor task. The test is only partially based on intact stereopsis, since monocular depth perception clues are involved. To overcome this shortcoming, a new test variant has been developed and tested. METHODS By covering the tip of the examiner's rod, monocular cues should be drastically reduced. Twenty normal subj...

The dominant perspective in discussions of labor and environmental standards and globalization is that of North-South competition and its impact on Northern standards. This paper presents an alternative perspective, that of South-South competition to export to the North, and its impact on Southern standards. It develops a simple model of Southern competition on standards, which can begin to pro...

We investigated whether specular highlights facilitate the perception of shape from shading in a search paradigm and how highlights interact with shading to facilitate this perception. Our results indicated that stimuli containing highlights led to shorter searching time with the dependence on the light source direction (top lights make searching faster), suggesting that highlights indeed facil...

In three behavioral experiments using depth-inverted visual stimuli, the factors that contribute to the 'reverse perspective' illusion were measured. The density of linear perspective grid lines was found to induce the illusion most strongly, followed by shading/shadows, and texture/color information. The relative contributions of such pictorial cues to depth perception are similar to those tha...

An important question in biology is how the relative size of different organs is kept nearly constant during growth of an animal. This property, called proportionate growth, has received increased attention in recent years. We discuss our recent work on a simple model where this feature comes out quite naturally from local rules, without fine-tuning any parameter. The patterns produced are comp...

We show that the discrete Heisenberg group has unbounded deadend depth with respect to every finite generating set. We also show that, in contrast, it has bounded retreat depth.

We present a system for visuo-auditory substitution that takes as input a depth map, and produces as output a corresponding melody. A real-time apparatus based on the Kinect R ©, a computer and a headphone, is developed within our team. Earlier experiment with the system shows that, when equipped, a sighted person temporary deprived from vision can therefore move in an unknown indoor environmen...